What analitic procedures are followed by laboratories to determine mineral content in humans? What are the standard procedures? Do they apply to plasma only?
There are some methods for urine, although they may be less accurate.
Our undergrads measure Na and K in diluted urine using flame photometry, Fe and Ca on wet ashed urine by ICP-OES, and Cl in diluted urine using a Chloride analyser.
I suspect the ICP-OES can be used for other minerals. Sorry, but I don't have any references.
each different mineral have different test pricnciple Yago. if you will specify the mineral about what you want to know, may be i can can help.
By the way, fully automated analyzer in general use colorymetry or turbidometry method to use mineral.
As example, calcium by OCPC method but its a colorimetric method. and u can use this method in urine also. As Terry said, ISE method is used to measure chloride, NA, Ionised calcium , Lithium etc.